Characteristics of Soil Nitrogen Transformation in Different Clonal Chinese Fir Plantations
[Objective]This study aimed to reveal the characteristics of soil nitrogen(N)transformation in different clonal Chinese fir plantations in Yangkou National Forest Farm of Fujian.This study provided theoretical basis for artificial nitrogen management and improved seed breeding of different clones of Chinese fir plantations.[Method]An incubation experiment was carried out with 7 different kinds of 15-year old third-generation excellent culture materials and seedlings(Y003,Y008,Y020,Y061,Y062,Ysec and Ymix)as the research objects,and the basic physical and chemical properties,net N mineralization and nitrification rate of soil of different clones were evaluated.[Result]The results showed that the net rates of N mineralization and nitrification were significantly affected by different clonal Chinese fir plantations.Specifically,the net mineralization rate and net nitrification rate were-0.09-0.118 mg·kg-1·d-1 and-0.021-0.051 mg·kg-1·d-1,respectively.During the whole incubation period,the average net N mineralization rate of Y061 was 0.117 mg·kg-1·d-1,which was significantly higher than that of other clones and followed by Ymix(0.046 mg·kg-1·d-1)and Y062(0.033 mg·kg-1·d-1).In contrast,the average net N mineralization rates of the other four clones were negative,indicating the occurrence of net N immobilization.The average net nitrification rate of the Y008 clone was the highest,which was 0.051 mg·kg-1·d-1,followed by Ymix(0.003 mg·kg-1·d-1)and Y020 clone(0.007 mg·kg-1·d-1).[Conclusion]The results showed that the soil N supply capacity and N retention capacity of Y061 and Y062 clones were significantly higher than those of other clones,and the risk of N loss such as leaching in Y008 clones was higher than that of other clones.Therefore,the clone species should be rationally selected to ensure the soil fertility supply in actual planting.This study provides a theoretical basis for artificial nitrogen management and improved seed breeding of different clones of Chinese fir plantations.
国家科技期刊平台
NSTL
万方数据
